G-SYNC 101: Control Panel


G-SYNC Module

The G-SYNC module is a small chip that replaces the display’s standard internal scaler, and contains enough onboard memory to hold and process a single frame at a time.

The module exploits the vertical blanking interval (the span between the previous and next frame scan) to manipulate the display’s internal timings; performing G2G (gray to gray) overdrive calculations to prevent ghosting, and synchronizing the display’s refresh rate to the GPU’s render rate to eliminate tearing, along with the delayed frame delivery and adjoining stutter caused by traditional syncing methods.

G-SYNC Demo

The below Blur Busters Test UFO motion test pattern uses motion interpolation techniques to simulate the seamless framerate transitions G-SYNC provides within the refresh rate, when directly compared to standalone V-SYNC.

G-SYNC Activation

“Enable for full screen mode” (exclusive fullscreen functionality only) will automatically engage when a supported display is connected to the GPU. If G-SYNC behavior is suspect or non-functioning, untick the “Enable G-SYNC, G-SYNC Compatible” box, apply, re-tick, and apply.

Blur Buster's G-SYNC 101: Control Panel

G-SYNC Windowed Mode

“Enable for windowed and full screen mode” allows G-SYNC support for windowed and borderless windowed mode. This option was introduced in a 2015 driver update, and by manipulating the DWM (Desktop Windows Manager) framebuffer, enables G-SYNC’s VRR (variable refresh rate) to synchronize to the focused window’s render rate; unfocused windows remain at the desktop’s fixed refresh rate until focused on.

G-SYNC only functions on one window at a time, and thus any unfocused window that contains moving content will appear to stutter or slow down, a reason why a variety of non-gaming applications (popular web browsers among them) include predefined Nvidia profiles that disable G-SYNC support.

Note: this setting may require a game or system restart after application; the “G-SYNC Indicator” (Nvidia Control Panel > Display > G-SYNC Indicator) can be enabled to verify it is working as intended.

G-SYNC Preferred Refresh Rate

“Highest available” automatically engages when G-SYNC is enabled, and overrides the in-game refresh rate selector (if present), defaulting to the highest supported refresh rate of the display. This is useful for games that don’t include a selector, and ensures the display’s native refresh rate is utilized.

“Application-controlled” adheres to the desktop’s current refresh rate, or defers control to games that contain a refresh rate selector.

Note: this setting only applies to games being run in exclusive fullscreen mode. For games being run in borderless or windowed mode, the desktop dictates the refresh rate.

G-SYNC & V-SYNC

G-SYNC (GPU Synchronization) works on the same principle as double buffer V-SYNC; buffer A begins to render frame A, and upon completion, scans it to the display. Meanwhile, as buffer A finishes scanning its first frame, buffer B begins to render frame B, and upon completion, scans it to the display, repeat.

The primary difference between G-SYNC and V-SYNC is the method in which rendered frames are synchronized. With V-SYNC, the GPU’s render rate is synchronized to the fixed refresh rate of the display. With G-SYNC, the display’s VRR (variable refresh rate) is synchronized to the GPU’s render rate.

Upon its release, G-SYNC’s ability to fall back on fixed refresh rate V-SYNC behavior when exceeding the maximum refresh rate of the display was built-in and non-optional. A 2015 driver update later exposed the option.

This update led to recurring confusion, creating a misconception that G-SYNC and V-SYNC are entirely separate options. However, with G-SYNC enabled, the “Vertical sync” option in the control panel no longer acts as V-SYNC, and actually dictates whether, one, the G-SYNC module compensates for frametime variances output by the system (which prevents tearing at all times. G-SYNC + V-SYNC “Off” disables this behavior; see G-SYNC 101: Range), and two, whether G-SYNC falls back on fixed refresh rate V-SYNC behavior; if V-SYNC is “On,” G-SYNC will revert to V-SYNC behavior above its range, if V-SYNC is “Off,” G-SYNC will disable above its range, and tearing will begin display wide.

Within its range, G-SYNC is the only syncing method active, no matter the V-SYNC “On” or “Off” setting.

Currently, when G-SYNC is enabled, the control panel’s “Vertical sync” entry is automatically engaged to “Use the 3D application setting,” which defers V-SYNC fallback behavior and frametime compensation control to the in-game V-SYNC option. This can be manually overridden by changing the “Vertical sync” entry in the control panel to “Off,” “On,” or “Fast.”



2231 Comments For “G-SYNC 101”

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Sort by:   newest | oldest | most liked
Vasko
Member
Vasko

Hello,

Would you please recommend the lowest latency setting for my pc in COD Cold War? I have the 360Hz Asus monitor and get between 280-310 fps during game play. I currently have the monitor set at 240Hz with unlimited fps, V-Sync and G-Sync off and it is very smooth. Would it be better to change the refresh rate to 300 or 360Hz even though the fps most likely average around 280? Does it make sense to turn G-Sync on?

Your help is highly appreciated!

Thank you,
Vasko

Tonaway
Member
Tonaway

Hello, I have a weird question.

Does G-SYNC still work if you lower the refresh rate (to something inside G-SYNC range) and use V-SYNC on in order to lock the FPS? Instead of running max refresh rate + V-SYNC on + -3 FPS lock.

For example: set refresh rate from 144hz to 120hz and activate V-SYNC so the game runs at 120 FPS and hz. In this case, will G-SYNC still be active? Or do you still have to set a FPS limiter to 117 FPS?

Will these settings have G-SYNC working as intended or will there be detriments to running games like this (except for running it at 120hz and 120 FPS, instead of 144hz and 141 FPS). If it works, does locking the FPS this way have any benefit over other ways of locking the FPS, and does it introduce normal V-SYNC latency if it hits 120 FPS?

fatehasfans
Member
fatehasfans

Hi there, is there an optimizing guide for Free-sync?

gaxode9376
Member
gaxode9376

what if a game only let you cap at a fixed refresh rate or unlimited rather than a custom value

DerConnor
Member
DerConnor

So what actually causes the tearing from “Upper & Lower Frametime Variances”? Is it because G-Sync is somehow unable to respond to a quick change in frametime (I read somewhere it uses a fixed polling frequency to update the current refresh rate)? And in the Valorant clips with the FPS capped to 142, shouldn’t this result in a constant frametime or is there some problem with how the FPS limiter works (introducing inconsistent frametimes)? I also can’t for the life of me see any tearing in the second Valorant clip.

Thanks a lot for this article, it was a super interesting and informative read.

wpDiscuz